The present invention relates to agricultural row crop planters; and more particularly, it relates to a row crop planter which includes conservation tillage apparatus on the planter.
For many years past, most farmers performed some deep tillage or plowing in the Fall after harvest or in the early Spring prior to planting, thinking this a necessary practice for maximum crop production. The plowing was accomplished by a moldboard plow, chisel plow or other implement, the purpose of which was to break up hard soil to a substantial depth, to bury trash such as stocks and other residue, and to bring up some of the deep soil. In the Spring, before planting, some farmers then performed secondary tillage and leveling operation, requiring a second pass over the field, to break up large clumps, pulvarize the soil and make it level. Following the seed bed preparation, a third pass of the land with the actual planter was normally required.
In recent times, farmers have become aware of the need to practice conservation techniques to preserve their most valuable asset, namely the rich soil in which the crops are grown. A principal way in which this is accomplished is to reduce the amount of primary or deep tillage prior to planting and to leave at least some of the trash at the surface of the soil. This prevents errosion by both wind and water run-off. Still further, with the advent of high fuel cost, the farmer has become increasingly aware of the economic advantages in reducing the number of passes over the land with the tractor. This has the added advantage of reducing the amount of time necessary to accomplish planting, permitting the farmer to plant more acreage and allowing him to take advantage of ideal planting conditions, both of which increase his income and make his operation more efficient.
Thus, in recent years, the farmer has become increasingly aware of the need to practice conservation tillage, and he has also educated himself to be aware of the trade-offs available between the practices of primary tillage, seed bed preparation and planting which reduce his expenses with little or no effect on the crop yield.
However, not all so-called conservation tillage systems presently available are effective in providing the farmer with a good crop yield while reducing the need for deep tillage or seed bed preparation. Further, those systems which have been found to be effective have not provided the farmer with the necessary versatility he needs to accomodate his planter system to various changes in soils or soil conditions, which vary from farm to farm or even field to field, and may change, if the farmer so desires for different crops.
Thus, a principal advantage and object of the present invention is the versatility and effectiveness that it provides in a conservation tillage row crop planter system, while permitting the entire system, including the tillage section, to operate at the higher speeds at which modern planting units are capable of operating. In the illustrated embodiment of the present invention, separate tillage and planting units are provided for each row, with the tillage unit mounted in a forward position to the planter frame by means of an independent four bar linkage which not only permits the depth of the planter unit to be independently set, but also isolates vertical excursions of the tillage unit, as in encountering heavy trash, rocks or lumps of hard soil, so that they do not affect the planting depth. The planting units then follow behind their associated tillage units.
A preferred form of the planter frame is a self-supporting pull-type frame having parallel forward and rear tool bars extending transverse of the direction of travel of the vehicle. The planter units, which may be conventional, are mounted behind the rear tool bar, each by its own four bar linkage. The tillage units are mounted between the forward and rear tool bars, each by its own independent four bar linkage which is connected to the rear tool bar so that the principal driving force for the tillage units is a pushing force rather than a pulling force, although this is not necessary to the practice of the invention. For lateral stability, the forward portions of the tillage units are mounted to the forward tool bar by a structure which prevents their lateral motion but which does not support any of the weight of the tillage units.
Each tillage unit includes a banded coulter followed by a pair of rolling row cleaning discs which are followed by a fluted coulter. The banded coulter sets the depth of the leading portion of the tillage unit and provides lateral stability to the unit, in combination with its mounting to the forward tool bar. Scrapers are provided for cleaning mud and trash from the banded coulter.
The row cleaning discs are arranged so that their leading edges overlap in a fore-to-aft direction to prevent accumulation of trash and debris. Further, the axes of rotation of the row cleaning discs are arranged so that the discs are inclined relative to the direction of travel and they face slightly downwardly to clear the trash to the side while avoiding clogging or plugging. The row cleaning discs are mounted to a common standard which is independently vertically adjustable on the subframe of the tillage unit. Although the operating depth of the row cleaning discs may be set continuously within a given range, it is contemplated that they will be set at one of three principal depths.
If the discs are set to a depth of approximately two inches (that is, the deepest portion of the trough formed by a disc lies nominally two inches below the surface of the soil), the discs will clear a path of approximately twelve to fourteen inches in width. This is referred to as the ridge planting or till-plant mode of operation. This mode of planting is advantageous in heavy soils or where it is desired to expose the soil above and lateral to the planted row to the sun's energy for quicker warming.
When the depth of the row cleaning discs is set to skim the surface of the soil so as to clear only surface residue, it is referred to as a minimum tillage mode of planting. This may be used where the farmer has previously used a chisel plow or disc harrow for Spring tillage. The higher setting of the row cleaning discs reduces fuel consumption while moving surface residue and larger clumps to the side for better gauging of planting depth.
The third principal mode for the row cleaning discs is to set them above the level of the ground so that they are not used. This setting is used for both the no-till mode of planting in which only the fluted coulter is used, as well as in the conventional planter mode in which the tillage unit is locked entirely in a raised position.
The row cleaning discs, as mentioned, are followed by a fluted or tillage coulter which works and loosens a narrow band of soil approximately two inches wide, depending upon the undulations of the coulter, and perhaps three inches deep--i.e., about the dimensions of a seed furrow. This facilitates furrow-opening by the planter which follows, and also loosens the soil in which the seed is to be planted to promote root development of the seedling and penetration of the soil by the developing plant.
Each tillage unit is provided with a weight adjusting mechanism for transferring weight from the rear tool bar to the tillage unit. The amount of weight transferred is continuously adjustable over a wide range to accomodate the tillage unit to variations in soil condition as well as to differences in operating speed of the system.
The present invention thus provides a planting system which is highly effective in accomplishing a desired amount of tillage at the same time row crops are planted, while adapting to a wide range of uses and preferences.
Other features and advantages of the present invention will be apparent to persons skilled in the art from the following detailed description of a preferred embodiment accompanied by the attached drawing.